Interstate SRM-24 Maintenance free???

[jimmarako]

OK, I'm actually embarrassed to ask this.

Just picked up our new trailer this week and I was pleasantly surprised to see the dealer actually installed 2 batteries. I didn't even request this. When I took a look there are 2 Interstate SRM-24 batteries wired together. Before joining this forum I thought that Interstates were a good brand to have. I generally have used Optimas when replacing batteries. It seems that all these brands are not all that good anymore(maybe??) so now I just go to Walmart. I know none of you guys would touch any of these for your RV, maybe some will for their TV.

Anyway, my previous trailer was clearly a serviceable battery with the 6 little round caps on top. Just like the battery for my sump, .... This interstate battery looks like every other car battery I've had/seen for 30+ years with just the 2 rectangular covers. Had I gone to AutoZone and bought this for my car I wouldn't have thought twice and just assumed it was the typical maintenance free battery. Since the RV dealer installed them on an RV I had expected batteries that required service. The Interstate web site doesn't seem to say either way.

I'm always plugged in when I camp or stored at home. I may leave it unplugged for several days when getting ready to leave and run the slides, jacks, etc,... as needed. So the batteries are abused, but I don't want to miss something simple like adding water while they sit doing nothing all winter.

Thanks
Jim M.

[A32Deuce]

There are other AGM batterys out there. I am trying 2 NAPA batterys now. 1 in my pickup at home and the other in my MH. Great so far. I got 9 to 13 years out of Optima batterys in the past.

[Jay2504]

The SRM 24 is a wet cell deep cycle battery. It is not a AGM battery. I don’t know if the covers can be pried open to add water or not. Usually these types have an extra water capacity designed to last the expected life of the battery. I would bet that those caps will come off, but I recommend contacting Interstate to see for sure. Jay

[bikendan]

What the dealer installed, were basic dual-purpose marine batteries. They are NOT true deep cycle batteries. They are a compromise between a starting battery and a deep cycle battery. I'll bet they have a CCA(cold cranking amps)rating.

[jimmarako]

Yes, they are 550CCA. Good thing they are not "starting batteries" thats a low CCA.

https://www.interstatebatteries.com/products/srm-24

I'm not looking for more work so if I don't have to check water levels, yea! Hopefully they last the 5-7 years my car batteries usually last. By then maybe lithiums will be more affordable and I'll go high tech.

Jim M.

[Blackrock]

I am running two of those on my 5th wheel and starting year number 5. Yes the rectangular cap comes off and you can add water Mine take a sip at the start of each season. The spend all winter plugged into shore power.

[TitanMike]

If you regularly camp with electricity hookups and only use the batteries for short intervals like jacks, slides, water pump while using the bathroom during a pit stop while traveling, these batteries will serve you well. Even for a chilly overnight in a parking lot along the way.


The issue is really deep cycling like when boondocking for a long weekend without recharging (solar or generator) when they reachthe magic 50% DOD.

Unless you need more than 60 amp hours of use on a regular basis before charging I'd just use them as long as they last. They're maintenance free but it wouln't hurt to pop the cell covers (the rectangular covers in the center of the battery) once in a while and just look at electrolyte levels. Chances are you won't need to bother with water until they are worn out several years from now.

[jimmarako]

Thanks all. I'll worry about it in 5+ years hopefully.....

Jim M.

[NMWildcat]

The srm24 is a marine/rv deep cycle. Maybe it doesn't meet the requirements for the deep cycle purists, but they work fine. I use the 27 series in mine and they last 4.5 to 5 years. We boondock most of the time and according to all the forum experts, we abuse them horribly. They still last about 5 years, and they are cheap.
Happy RVing!

[Ejs4029]

Originally Posted by NMWildcat

The srm24 is a marine/rv deep cycle. Maybe it doesn't meet the requirements for the deep cycle purists, but they work fine. I use the 27 series in mine and they last 4.5 to 5 years. We boondock most of the time and according to all the forum experts, we abuse them horribly. They still last about 5 years, and they are cheap.
Happy RVing!

X2....I've been using a SRM24 for almost 6 years now. I don't boondock and remove the battery in Winter and put it on a trickle charger. I would certainly buy another when it's time a for a new one.

[NMWildcat]

Originally Posted by Ejs4029

X2....I've been using a SRM24 for almost 6 years now. I don't boondock and remove the battery in Winter and put it on a trickle charger. I would certainly buy another when it's time a for a new one.

Exactly. And the good thing about Interstates is that you can find them everywhere, even in Podunk USA!

[Tundra 2014]

Where the adhesive strip is on top of the battery peels off to show the 6 caps. If I was replacing I would go to 2-6 volt golf cart batteries. Same cost, more capacity. Really depends on how much you boondocks, and how you handle batteries in the off season.

[DustyRoads]

If those are the same as mine they only have 64amp hrs each for a total of 128 amp hrs. If dry camping they will only last about 3 to 4 days. I will be going to 2x 6volt this spring. However, if you are going to be plugged in at campgrounds they will be fine.

[1953m38a1]

Went out to the MH this AM, to start up and exercise generator, check systems etc. Part of my check over is the batteries electrolyte levels. They sit on the on board charger/converter for long periods of time and I am aware of the damage that can ensue from running dry. They are Interstate SPM24 and seem to be holding up well, they take a thimbleful in a couple of cells. The thing that I find unreal is the sold dating. The unit is a 2008 Itasca Suncruiser 38T, but it has 2 SPM24s dated as 2003/Sept. They work well and at 18 years old seem unreal....but no complaints

[TitanMike]

Originally Posted by 1953m38a1

Went out to the MH this AM, to start up and exercise generator, check systems etc. Part of my check over is the batteries electrolyte levels. They sit on the on board charger/converter for long periods of time and I am aware of the damage that can ensue from running dry. They are Interstate SPM24 and seem to be holding up well, they take a thimbleful in a couple of cells. The thing that I find unreal is the sold dating. The unit is a 2008 Itasca Suncruiser 38T, but it has 2 SPM24s dated as 2003/Sept. They work well and at 18 years old seem unreal....but no complaints

Battery life is mainly determined by how well they are cared for. Not discharged below 50% then recharged ASAP. Regular monitoring of electrolyte levels.

As for the sold date on your batteries are you sure that "2003" isn't actually a "2003" with the left side of the "8" scuffed off??

[jimmarako]

I forgot I started this post way back when. So since I posted I dug around the Interstate battery site and hidden away somewhere found the statement that the Interstate SRM batteries are indeed maintenance free, unless you use them in a trailer/RV. Then you need to regularly check the water level. So there you go.
I'll say I'm inspired by NMWildcat's use of the wrong battery to boondock and getting 4-5 years out of them. An here I thought lithium would be the way to go next time.
Thanks
Jim M.

[TitanMike]

Originally Posted by jimmarako

I forgot I started this post way back when. So since I posted I dug around the Interstate battery site and hidden away somewhere found the statement that the Interstate SRM batteries are indeed maintenance free, unless you use them in a trailer/RV. Then you need to regularly check the water level. So there you go.
I'll say I'm inspired by NMWildcat's use of the wrong battery to boondock and getting 4-5 years out of them. An here I thought lithium would be the way to go next time.
Thanks
Jim M.

Regular Lead/Acid batteries still work well for some. The Lithium batteries just work a lot better for many. Lighter weight, more usable capacity in the same footprint, faster charging, no "voltage sag" when running a high current device like a 2kw Inverter, longer life, etc.

It's all a matter of choice. If the lights go on and the furnace runs when you are cold, and you are happy with the maintenance chores, charging time, etc, it's just fine by me.

[1953m38a1]

Thanks for the reply, TitanMike in 15. Went out and double checked scratch off year and month on batteries. Unless the PO did just that with old eyes and scratched the 3 instead of the 8, the evidence is very definitely the 3 scratched out. Not complaining! Not broke...don't fix it. Cheers

[TitanMike]

Originally Posted by 1953m38a1

Thanks for the reply, TitanMike in 15. Went out and double checked scratch off year and month on batteries. Unless the PO did just that with old eyes and scratched the 3 instead of the 8, the evidence is very definitely the 3 scratched out. Not complaining! Not broke...don't fix it. Cheers

No argument on "if it works".

Just keep em charged and electrolyte at proper level.